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Noisy Compressor

Ace Barker on Thu August 14, 2008 9:30 PM User is offline

Year: 1999
Make: Chevrolet
Model: Lumina LTZ
Engine Size: 3.8
Refrigerant Type: R134a
Ambient Temp: 78
Pressure Low: 28
Pressure High: 210
Country of Origin: United States

When starting car with AC on, high pitch whine. Turn off AC whine partially went away and I found water pump was making noise as well. Replaced pump. Partial noise gone.

Started car compressor whine still there. Turning off AC makes the whine go a way. Shut car off. Removed belt and spun compressor. Spins freely but seems to have a gravely sound.

Running car about five minutes seems to quiet down.

Vent temps were around 48-50. Seems cool but seems it could be colder.

My daughter is headed off to school next weekend. I am concerned the compressor is failing.

I didn't run a leak check. Also this car has about 135K on it and the AC has never been touched.

Any suggestions?



Edited: Thu August 14, 2008 at 9:36 PM by Ace Barker

GM Tech on Fri August 15, 2008 8:15 AM User is offline

As long as you are sure it's the compressor- (whines usually are alternator IMO) then the compressor pulley bearing may be in early stages of can be replaced separately..

The number one A/C diagnostic tool there is- is to know how much refrigerant is in the system- this can only be done by recovering and weighing the refrigerant!!
Just a thought.... 65% of A/C failures in my 3200 car diagnostic database (GM vehicles) are due to loss of refrigerant due to a leak......

mk378 on Fri August 15, 2008 8:41 AM User is offline

That gravely sound is indeed the bearing going bad, it will get a lot louder at speed and with the load of the belt on it. Spinning a compressor pulley by hand should be almost silent. You can change it without buying a whole compressor, and also it is done with the system staying charged with refrigerant so no need to evacuate and recharge it.

Ace Barker on Fri August 15, 2008 10:24 AM User is offline

Thanks everyone for the quick replies. I fired up the car this morning. The pulley is singing with the compressor off. I went ahead and bought a new Delco compressor, accumulator, flush and orifice tube this morning. Its easier for me to replace it all. I don't have the tools to pull the clutch and bearings out after looking at my GM Service manual. If I a missing somethin ghere, let me know though.

I need to get the systems evacuated today.

Do these compressors come with oil? I have new bottle of AC Delco refrigerant oil for R134a. Part number 15-118 12356151. It reads it must be used with GM Harrison manufactured componenets using R134a. Can I use this oil?

Does anyone know how much oil to add to this system? how much in the compressor and how much in the accumulator?

In addition, what are good lo and high pressure numbers? Ambient temperature should reach around 85 to 90 today.



mk378 on Fri August 15, 2008 1:55 PM User is offline

The V5 has an oil sump. Remove the oil plug from the side of the new compressor and drain any oil that it may have come with. That oil shouldn't be used because it could have absorbed water during storage. Then I think you need 8 oz of new oil in it (check that amount). Also put about 1 oz in your new accumulator. No need to flush the system.

Ace Barker on Fri August 15, 2008 2:27 PM User is offline

Thanks MK. The Delco Oil should be OK? Going to pick the parts up in a few minutes. I will look up the capacity chart.

01-98 All Eng. .............................................................................................. R-134a 36.00 PAG-150 9.00 409501 409883. You are right 9 ounces.

I also found this chart. The oil I have AC Delco 15-118 12356151 is 150 viscosity. I am confused on which oil to use.

Compressor Type Supplied through GMACDelco Viscosity ACDelco Part Number GM Part Number
Radial R-4 All R-134a 150 15-118 12356151
A6 All R-134a 150 15-118 12356151

Compressor Type Viscosity ACDelco Part Number GM Part Number
All other ACDelco supplied compressors All R-134a 46 10-5040 (8oz. Bottle) 10-5026 (8 oz. Cartridge) (1) 89022191 88901445


Edited: Fri August 15, 2008 at 2:40 PM by Ace Barker

Ace Barker on Fri August 15, 2008 4:13 PM User is offline

Well the AC Delco parts man I have used for years called checked and was told to use PAG 46 not PAG 150. He was surprised to hear this. Thoughts? I bought PAG 46. It seems to match my earlier post since this is a V5 it matches the all other category in the previous post.



Ace Barker on Fri August 15, 2008 4:37 PM User is offline

This is my last post on this. My GM Manual calls for 9 ounces of GM Part Number, 12345923, PAG 150, PAG BLUE. I have PAG 46 and PAG 150. Will search around for some PAG Blue.



Chick on Fri August 15, 2008 6:33 PM User is offlineView users profile

Are you flushing the system? If not, you don't need to add back 9 ounces.. You will have to much oil in the system..Pag 150 for GM compressors, although I do use PAG blue in V5 compressors, and the bottles I still have say PAG 125..

Email: Chick


Freedoms just another word for nothing left to lose

Ace Barker on Sat August 16, 2008 10:53 AM User is offline

Thanks Chick!

I pulled the orifice tube and it was clean. I went to the GM dealer this morning and they said they use PAG 46. Can I just use normal PAG 150 not PAG 150 blue? I am afraid to go mixing PAG 150 and PAG 46. That seems it would cause problems.

Since I am not flushing, I will measure what comes out of the compresssor and replace that. How much to put in the accumulator/sryer?



iceman2555 on Sat August 16, 2008 11:49 AM User is offlineView users profile

The question of lubricants in GM compressors comes up each year during discussions at trade shows.

A simple, yet, quite reasonable answer is that Delco (dealers) typically service mostly NEW vehicles. GM (new) vehicles use compressors from various manufacturers. It is more likely to see a Denso made compressor on a late model GM than it is to see a GM or GM subsidy made unit. Denso recommends PAG 46 for many of their GM compressors...hence the parts man suggestion of PAG 46.
Delphi (GM subsidy) normally services the aftermarket...your vehicle...1999.....and they specify PAG 125-135 (PAG 150). The compressor on your vehicle should be using PAG 150 or PAG Blue (135).
Possible damage could occur to the compressor is PAG 46 is used.

The most important that the system is completely and properly recharged...unfortunately an attempt to insure proper recharge using pressures as a guide is almost impossible with this compressor for a novice (DIYER). A suggestion would be to complete the work....have the system recharged by a competent shop that can utilize the correct recharge procedures.
The other down side to this are not flushing the this point how much lubricant to add to the system becomes as best.....a SWAG.....Scientific Wild Ass Guess!!!!

There are two very important variables to a proper ac repair that should be the amount of refrigerant within the system....(recharge)...and two...the total amount of lubricant within the system. Test have proven that at app. a 50% over charge of lubricant....possible reed valve problems may begin to occur.

Why not take the time to completely clean the system...on this vehicle it is very easy and can be accomplished with a minimum amount of time.
Failure to insure that the compressor is completely charged....will result in damage to the pivot bearing in this compressor. The pivot bearing is lubricated by a pressure differential within the system and will insure correct lubrication to this vital area. Missing the charge rate by only a few ounces may result in this failure. Keep in mind that during the recharge procedure, if using cans and pressures, this area could be operational with no lubricant migration. Ya Takes Ya Chances!!!!

Had some lovely photos of this problem...however for some 'upward fornication' they will not upload!!!!

The strongest reason for the people to retain the right to keep and bear arms is, as a last resort, to protect themselves against tyranny in government.
Thomas Jefferson

Ace Barker on Sat August 16, 2008 5:04 PM User is offline


Thanks! I am a DIYER for sure. What I do for a living is much different than this but I have always bee interested in HVAC.

Anyway, I did put the PAG 150 in. Belive it or not, I actually found Interdyne is blue.

I went ahead and flushed the system, ran air through it and let it set for a while. I put in 9 ounces of oil since it was flushed. Everything came out clean. Replaced the O rings with Nylog and buttoned it back together. Pulling a vaccuum now.

I did put 1 in the dryer and 8 in the compressor. The AC compressor was shipped dry.

I have started charging. Not sure if I do it myself or take it somewhere.



Ace Barker on Sat August 16, 2008 8:15 PM User is offline

Thanks everyone. So far so good. around 40 at the vents. No compressor noise. Let it run a long time today at idle. Still learning. I had to put 1.88 lbs. We figured about 2 and a 1/2 (guesstimate) cans. My wife is a chemist at CDC. She is probably more qualified to do this than me.


NickD on Sun August 17, 2008 9:00 AM User is offline

GM compressor pulley bearings use to last well over 200K miles, now they are making noise at around 70-80K, reason, very little or next to nothing grease in them. I even clean and add grease to brand new bearings. Why? I want them to last. Had problems with my 04 Chevy with the upper strut thrust bearings, when I took them apart found rusty balls, they were too far gone to clean and regrease. But did open the brand new ones, a very thin coat of grease on each ball. Find the same thing on alternator and idler pulley bearings, must be a conspiracy.

Besides the lack of grease, they made them almost impossible to change, could pop out a bearing on an old A6 in no time, but didn't have too.

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